JVM Agent

Another variant is Jolokia's JVM agent which does not need any special container environment. The only dependency is on Oracle's JDK 6 or later as runtime, since it contains a lightweight HTTP Server used for exporting the Jolokia protocol. This agent is the most generic one which can instrument any Java application using a JDK6. It is suitable for situations where the other agents don't fit. Also, it can be used for dynamically attaching an agent to a running Java process.

For using this agent, the following argument to the Java application to instrument has to be given:

  -javaagent:/path/to/jolokia-jvm-<version>-agent.jar

By default, the agent will listen on port 8778, but this can be configured as well as other aspects like authentication:

• Provide options on the commandline as key-value pairs:

    -javaagent:agent.jar=port=7777,host=localhost

• Via a properties file

    -javaagent:agent.jar=config=/path/to/config.properties

• Via packaging a jolokia-agent.properties top level in the agent.jar

Options are used in the given precedence, the former overwriting the later values.

For attaching the agent dynamically to a running Java process, the following command can be used to get a quick help

  java -jar /path/to/jolokia-jvm-<version>-agent.jar --help

For more details and usage examples please refer to the reference manual.